This invention relates to electrostatic devices for the gating of light, and more particularly to such devices having an electrostatically actuated resilient electrode and a fixed electrode for use as a display device.
Such electrostatic devices having a curved fixed electrode and an adjacent resilient sheet electrode are described in my U.S. Pat. No. 3,897,997 issued Aug. 5, 1975 and in my application Ser. No. 711,710 filed Aug. 4, 1976. These devices permit the change in appearance of the fixed electrode from a dark to a light hue, or visa versa, by application of appropriate electrical signals.
Other electrostatic devices have a variable electrode that is at rest in the form of a spiral roll. It unrolls upon being attracted electrostatically to an adjacent fixed electrode which fixed electrode may be a transparent plate. Such rolling electrode devices are described in U.S. Pat. No. 3,989,357 issued Nov. 2, 1976.
It is an object of this invention to provide an improved electrostatic display device having a sharply defined window area that is capable of changing from a dark to a light hue in response to an electrical signal.